“…there’s no success like failure, and…failure’s no success at all”—from the song Love Minus Zero/No Limit by Bob Dylan
On a mid-April visit to our cabin at Quiver Lake, near Chautauqua National Wildlife Refuge, I was looking for signs of the advancing season, such as flowering plants and bird sightings. Then, over the brisk winds blowing off the lake, there came, from the flooded black willow forest across the lake, the unmistakable guttural sounds of double-crested cormorants. They were re-establishing their nesting colony of the previous year, which had failed for unknown reasons by early May; they simply left, all of the nests abandoned.
This year I vowed to keep better track of the situation. I was not sure when the colony became active again, but it was definitely not active two weeks before this recent cabin visit. So, with eight weeks or more for egg incubation and time to fledge, I was expecting to see and hear a lot of cormorant activity this year. When conditions were right, I would canoe over to the colony for a closer look.
But by my next visit on May 4th, the cormorants had already abandoned the colony! I kept hoping that I was wrong and that they were all out foraging for fish, but if that were the case, I should have seen cormorants coming and going. During the intervening days since the last cabin visit, the Illinois River had dropped quite a bit, and since the river is connected to Quiver Lake, the lake level had also fallen. I wondered if the dry ground under the colony had given predators, such as raccoons, easy access to the nests. Was that the reason the cormorants abandoned their colony? I wanted to take a closer look, but time and opportunity did not converge until twelve days later.
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Cottonwood seeds floated in the air like a light snow flurry and this year’s crop of silver maple seedlings grew well during the longer days of mid-May, in some areas forming lines parallel to the lakeshore, marking a previous high-water level. The river itself had probably already hit its peak spring flood, and would be slowly falling toward its normal summer low period, but that would only be an average expectation; another big flood would not really be surprising.
At the lake’s shoreline, I was surrounded by vigorous bird songs and calls from house wrens, warbling vireos, Carolina wrens, Baltimore orioles, rose-breasted grosbeaks, and bobwhite quail. Yellow-billed cuckoos had already arrived, which for me signaled the end of the spring migration, but there were still some Tennessee warblers passing through on their way to the boreal forests of Canada. Buffalo gnats were becoming annoying—as they always are in May—but to endure them, I reminded myself of the fact that insects of all kinds are the protein source needed to grow healthy nestlings that must be ready to fly before too long. All of these environmental cues together formed the backdrop to the advancing bird breeding season, and I imagined those cues to be a strong reinforcement of the drive to reproduce. And yet, the cormorants abandoned their colony. I launched my canoe with little delay, and in the time it took for only a few strokes of the paddle, I was on the far side of the lake, heading for the failed cormorant colony.
It was almost like a dystopian scene, with all of the abandoned nests in surrounding trees appearing newly rehabilitated but completely unused. An active colony would be chaotic, with tree branches and leaves covered in bird droppings and messes. It seemed like such a waste, after going through all of the trouble to migrate to Illinois and then assemble at this particular location, to engage in numerous flights back and forth to gather so much nesting material of twigs and larger sticks, and then, somehow collectively to make the decision to give up and leave. How would they even communicate such a decision throughout the colony? I can imagine some individual birds giving up and moving on for whatever reason, and some birds staying, but for all of them to leave, there must have been a compelling reason.
Abandoned double-crested cormorant colony at Quiver Lake, 16 May 2023
Was it, in fact, predation? Or could they have been somehow harassed into leaving? In some circles, the fish-eating double-crested cormorant is not a popular bird. It’s curious that the colony was abandoned two years in a row. And a similar sequence of events happened in 2019: There was an active cormorant colony by the third week of April, and it was abandoned sometime between then and the middle of May. Before that, since 2011 when we acquired our cabin, either there was not a colony at Quiver Lake bottoms or I never noticed one if it was there.
In the end, double-crested cormorant colonies will succeed somewhere and fail elsewhere, maybe more failures than successes. Otherwise, the population might grow exponentially to the point where we would have so many cormorants (individuals live for six years on average), a population crash— related to an increase in diseases and overexploitation of habitat and food resources—would be inevitable. Their reproductive drive accounts for failure. That’s why each pair usually raises three or four young each year, sometimes with two broods. As another example: Why does a cottonwood tree produce so many seeds, when most of them never germinate? How many years must go by before even one makes it into a tree? What would the landscape look like if all of the seeds each year grew into trees? At any rate, it seems that the Quiver Lake cormorant colony might be due for success. For this year, though, they’ve apparently run out of time.
References
Dorr, B.S., K.L. Sullivan, P.D. Curtis, R.B. Chipman, and R.D. McCullough. 2016. Double-crested cormorants. Wildlife Damage Management Technical Series. U.S. Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services.
Kleen, V.M., L. Cordle, and R.A. Montgomery. 2004. The Illinois breeding bird atlas. Illinois Natural History Survey Special Publication No. 26. xviii + 459 pp.